scholarly journals COMPUTERIZED NONDESTRUCTIVE CHECK OF MATERIAL POROSITY

2016 ◽  
Vol 2016 (2) ◽  
pp. 138-142
Author(s):  
Юлия Можегова ◽  
Yuliya Mozhegova
Keyword(s):  
Gas Flow ◽  
Material Structure ◽  
Flow Through ◽  
Experimental Researches ◽  
Nondestructive Check ◽  
Material Porosity

This paper reports the mathematical dependence of material porosity on material structure and conditions of gas flow through material controlled. The design of the device for porosity nondestructive check and a principle of its operation are presented. The results of experimental researches carried out on the products of complex ceramic systems are shown. The accuracy in porosity control on the device offered is substantiated and the recommendations for its use in production are made.

INVESTIGATION OF THE TIME OF GAS FLOW THROUGH A HOLE IN LONG PIPELINES UNDER HIGH PRESSURE

2020 ◽  
Vol 58 (1) ◽  
pp. 30-43
Author(s):  
N.D. Yakimov ◽  
◽  
A.I. Khafizova ◽  
N.D. Chichirova ◽  
O.S. Dmitrieva ◽  
...  
Keyword(s):  
High Pressure ◽  
Gas Flow ◽  
Flow Through

Free area for gas flow through sieve plates with a bubbled bed

1975 ◽  
Vol 40 (11) ◽  
pp. 3315-3318 ◽  
Author(s):  
M. Rylek ◽  
F. Kaštánek ◽  
L. Nývlt ◽  
J. Kratochvíl
Keyword(s):  
Gas Flow ◽  
Flow Through ◽  
Sieve Plates ◽  
Free Area

scholarly journals A Study on Liquid Leak Rates in Packing Seals

2021 ◽  
Vol 11 (4) ◽  
pp. 1936
Author(s):  
Abdel-Hakim Bouzid
Keyword(s):  
Environmental Protection ◽  
Liquid Flow ◽  
Environmental Protection Agency ◽  
Gas Flow ◽  
Outer Boundary ◽  
Health And Safety ◽  
Toxic Substances ◽  
Packing Materials ◽  
Thickness Change ◽  
Flow Through

The accurate prediction of liquid leak rates in packing seals is an important step in the design of stuffing boxes, in order to comply with environmental protection laws and health and safety regulations regarding the release of toxic substances or fugitive emissions, such as those implemented by the Environmental Protection Agency (EPA) and the Technische Anleitung zur Reinhaltung der Luft (TA Luft). Most recent studies conducted on seals have concentrated on the prediction of gas flow, with little to no effort put toward predicting liquid flow. As a result, there is a need to simulate liquid flow through sealing materials in order to predict leakage into the outer boundary. Modelling of liquid flow through porous packing materials was addressed in this work. Characterization of their porous structure was determined to be a key parameter in the prediction of liquid flow through packing materials; the relationship between gland stress and leak rate was also acknowledged. The proposed methodology started by conducting experimental leak measurements with helium gas to characterize the number and size of capillaries. Liquid leak tests with water and kerosene were then conducted in order to validate the predictions. This study showed that liquid leak rates in packed stuffing boxes could be predicted with reasonable accuracy for low gland stresses. It was found that internal pressure and compression stress had an effect on leakage, as did the thickness change and the type of fluid. The measured leak rates were in the range of 0.062 to 5.7 mg/s for gases and 0.0013 and 5.5 mg/s for liquids.

Modeling and Calculation of Initial Ignition Gas Pressure Flow through the Rigid Porous Media in 100 mm Ignition Simulator

2012 ◽  
Vol 560-561 ◽  
pp. 1103-1113
Author(s):  
Zheng Gang Xiao ◽  
Wei Dong He ◽  
San Jiu Ying ◽  
Fu Ming Xu
Keyword(s):  
Porous Media ◽  
Gas Flow ◽  
Ceramic Composite ◽  
Peak Position ◽  
Chamber Pressure ◽  
Lateral Side ◽  
Physical Processes ◽  
Local Permeability ◽  
Pressure Peak ◽  
Flow Through

To acquire better understanding of the early ignition phenomena in 100mm ignition simulator loaded with packed propellant bed, a theoretical model of ignition gas flow through rigid porous media is developed. Three pressure gauges are installed in the lateral side of ignition simulator for chamber pressure measurements after ignition. The pseupropellant loaded in the chamber is similar to the standard 13/19 single-base cylindrical propellant in size. It is composed of rigid ceramic composite with low thermo conductivity. It is assumed that the pseupropellant bed is rigid in contrast to the previous elastic porous media assumption. The calculated pressure values can be verified by the experimental data well at the low loading density of pseupropellant bed of 0.18 g/cm3. However, there is still error between the experimental and calculated results in the early pressure peak position close to the ignition primer when the loading density of pseupropellant bed increases to 0.73 and 1.06g/cm3, due to the change of local permeability of pseupropellant bed at high loading density, which is assumed a constant in the model for the modeling easily. The calculations can enable better understanding of physical processes of ignition gas flow in the ignition simulator loaded with the pseupropellant bed.

Mixing Enhancement of Two Gases in a Microchannel Using DSMC

2013 ◽  
Vol 307 ◽  
pp. 166-169 ◽  
Author(s):  
Masoud Darbandi ◽  
Elyas Lakzian
Keyword(s):  
Gas Flow ◽  
Flow Analysis ◽  
Direct Simulation Monte Carlo ◽  
Equilibrium Composition ◽  
Mass Composition ◽  
Mixing Enhancement ◽  
Mixing Process ◽  
Result Section ◽  
Flow Through ◽  
Simulation Monte Carlo

Microgas flow analysis may not be performed accurately using the classical CFD methods because of encountering high Knudsen number regimes. Alternatively, the gas flow through micro-geometries can be investigated reliably using the direct simulation Monte Carlo (DSMC) method. Our concern in this paper is to use DSMC to study the mixing of two gases in a microchannel. The mixing process is assumed to be complete when the mass composition of each species deviates by no more than ±1% from its equilibrium composition. To enhance the mixing process, we focus on the effects of inlet-outlet pressure difference and the pressure ratios of the incoming CO and N2 streams on the mixing enhancement. The outcome of this study is suitably discussed in the result section.

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